Enhanced Conversions are one of the most effective ways to win back Google Ads conversions you'd otherwise lose to ad-blockers and ITP. They work by attaching hashed first-party data to a conversion — and this is exactly where server-side tracking excels.
What Enhanced Conversions are
In classic measurement, Google Ads matches a conversion to an ad click via the gclid stored in a cookie. When the cookie is missing (ad-blocker, expired ITP window), the match fails and the conversion isn't counted. Enhanced Conversions add a second path: they send hashed first-party data with the conversion — typically email, optionally phone or name and address — that the customer entered at checkout. Google matches it against its signed-in users and attributes the conversion even without a cookie.
Why it matters
- Recovers conversions lost to blocked cookies and short ITP lifetimes.
- Improves attribution and therefore automated bidding strategies (tROAS, maximize conversions).
- Data is sent hashed (SHA-256), so Google never receives the email in readable form.
Where server-side makes the difference
Enhanced Conversions can be deployed client-side via web GTM, but they hit the same limits as any client-side measurement — an ad-blocker blocks the whole request. A server-side setup sends the conversion with hashed data from the server via the Google Ads API, so it gets through even where client-side would fail. And you handle hashing and sending in one place, not tag by tag.
How to deploy it
- 1. Make sure the thank-you page (or purchase event) passes the customer's email into the data layer.
- 2. In the server-side GTM container, map the email (and any other available identifiers) into the conversion tag's user data.
- 3. DataNostro handles hashing and sending via Google Ads for you — just connect the account. The steps are in the docs: Google Ads server-side conversion tracking.
- 4. Verify in Google Ads diagnostics that Enhanced Conversions are received and the match rate is rising.
GDPR and consent
Enhanced Conversions process personal data, so they need the visitor's consent. Only send them when you have the appropriate consent — the server-side container is the ideal place to enforce that. See Consent Mode v2 in practice.
Summary
Enhanced Conversions are a cheap way to get more accurate data out of Google Ads — and server-side makes them reliable. Combined with first-party data and Consent Mode v2, they form a modern, GDPR-friendly foundation for performance measurement. See Google Ads via DataNostro or read the complete guide to server-side tracking.